Add Perth and PixelSeal benchmark oracles

tests/test_perth_oracle.py

@@ -0,0 +1,31 @@
+"""Tests for the pinned Perth oracle's pure contract."""
+
+from __future__ import annotations
+
+import sys
+from pathlib import Path
+
+SCRIPTS = Path(__file__).resolve().parents[1] / "scripts"
+if str(SCRIPTS) not in sys.path:
+    sys.path.insert(0, str(SCRIPTS))
+
+import perth_oracle  # noqa: E402
+
+
+def test_detection_rule_is_upstream_round_at_one_half() -> None:
+    assert perth_oracle.PerthReading(0.499).detected is False
+    assert perth_oracle.PerthReading(0.5).detected is False
+    assert perth_oracle.PerthReading(0.501).detected is True
+
+
+def test_checkpoint_and_source_are_immutable_pins() -> None:
+    assert len(perth_oracle.SOURCE_COMMIT) == 40
+    assert len(perth_oracle.CHECKPOINT_SHA256) == 64
+    assert all(char in "0123456789abcdef" for char in perth_oracle.CHECKPOINT_SHA256)
+
+
+def test_perth_has_no_message_payload_contract() -> None:
+    reading = perth_oracle.PerthReading(0.75)
+
+    assert not hasattr(reading, "decoded_bits")
+    assert not hasattr(perth_oracle, "message_bits")

tests/test_pixelseal_oracle.py

@@ -0,0 +1,64 @@
+"""Tests for the pinned PixelSeal oracle's pure helpers."""
+
+from __future__ import annotations
+
+import importlib
+import sys
+from pathlib import Path
+
+import pytest
+
+SCRIPTS = Path(__file__).resolve().parents[1] / "scripts"
+if str(SCRIPTS) not in sys.path:
+    sys.path.insert(0, str(SCRIPTS))
+
+import pixelseal_oracle  # noqa: E402
+
+
+class TestMessage:
+    def test_message_is_deterministic_and_256_bits(self) -> None:
+        first = pixelseal_oracle.message_bits()
+        second = pixelseal_oracle.message_bits()
+
+        assert first == second
+        assert len(first) == 256
+        assert set(first) <= {0, 1}
+
+    def test_seed_changes_the_message(self) -> None:
+        assert pixelseal_oracle.message_bits(seed=8) != pixelseal_oracle.message_bits(seed=7)
+
+
+class TestReading:
+    def test_label_is_hex_of_decoded_bits(self) -> None:
+        reading = pixelseal_oracle.PixelSealReading(1.0, tuple([1] * 8 + [0] * 8))
+
+        assert reading.label == "ff00"
+
+    def test_detection_rule_is_the_documented_adapter_threshold(self) -> None:
+        assert pixelseal_oracle.PixelSealReading(0.899, ()).detected is False
+        assert pixelseal_oracle.PixelSealReading(0.9, ()).detected is True
+
+
+class TestPins:
+    @pytest.mark.parametrize(
+        "value",
+        [pixelseal_oracle.CHECKPOINT_SHA256, pixelseal_oracle.MODEL_CARD_SHA256],
+    )
+    def test_digests_are_sha256(self, value: str) -> None:
+        assert len(value) == 64
+        assert all(char in "0123456789abcdef" for char in value)
+
+    def test_source_commit_is_pinned(self) -> None:
+        assert len(pixelseal_oracle.SOURCE_COMMIT) == 40
+
+
+def test_cache_dir_env_override_is_honored(monkeypatch: pytest.MonkeyPatch, tmp_path: Path) -> None:
+    original_cache = pixelseal_oracle.CACHE_DIR
+    try:
+        with monkeypatch.context() as environment:
+            environment.setenv("PIXELSEAL_CACHE_DIR", str(tmp_path / "cache"))
+            importlib.reload(pixelseal_oracle)
+            assert tmp_path / "cache" == pixelseal_oracle.CACHE_DIR
+    finally:
+        importlib.reload(pixelseal_oracle)
+    assert original_cache == pixelseal_oracle.CACHE_DIR

tests/test_watermark_benchmark.py

@@ -393,10 +393,12 @@ def test_jsonl_writer_refuses_overwrite_and_emits_strict_json(tmp_path: Path) ->
 def test_builtin_adapters_name_their_exact_source_files() -> None:
     adapters = MODULE.default_adapters()
 
-    assert set(adapters) == {"dwt-dct", "trustmark", "audioseal", "videoseal"}
+    assert set(adapters) == {"dwt-dct", "trustmark", "pixelseal", "audioseal", "perth", "videoseal"}
     assert adapters["dwt-dct"].source_file.name == "invisible_watermark.py"
     assert adapters["trustmark"].source_file.name == "trustmark_detector.py"
+    assert adapters["pixelseal"].source_file.name == "pixelseal_oracle.py"
     assert adapters["audioseal"].source_file.name == "audioseal_oracle.py"
+    assert adapters["perth"].source_file.name == "perth_oracle.py"
     assert adapters["videoseal"].source_file.name == "videoseal_oracle.py"
 
 
@@ -741,6 +743,20 @@ def test_detection_record_omits_temporal_for_non_temporal_adapters() -> None:
     assert "temporal" not in MODULE._detection_record(outcome, "not_detected", None)
 
 
+def test_detection_record_carries_message_accuracy_and_presence_score() -> None:
+    outcome = MODULE.DetectorOutcome(
+        status="detected",
+        label="fixed-message",
+        message_bit_accuracy=0.996,
+        score=0.75,
+    )
+
+    record = MODULE._detection_record(outcome, "detected", 2.0)
+
+    assert record["message_bit_accuracy"] == 0.996
+    assert record["score"] == 0.75
+
+
 def test_run_benchmark_records_videoseal_temporal_evidence(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> None:
     if shutil.which("ffmpeg") is None:
         pytest.skip("video rows decode through the system ffmpeg")